Six people indicted in connection with the deadly July 1, 2025 explosion at a fireworks storage facility in Esparto have made their first appearances in Yolo County court.
The Yolo County District Attorney’s Office filed dozens of charges against eight people in total. Prosecutors accuse them of running a “decade-long conspiracy” that turned the Esparto property into the “Northern California hub for an illegal enterprise that imports and sells illegal explosives on the black market.”
The most serious charges are seven counts of second-degree murder, one for each victim in the explosion, filed against five defendants — Samuel Machado, Kenneth Chee, Jack Lee, Gary Chan and Douglas Tollefsen. Three others — Tammy Machado, Craig Cutright and Ronald Botelho III — face a variety of other charges.
The Machados, who were both employees of the Yolo County Sheriff’s Office at the time of the explosion, owned the property where the storage facility was located. Chee is the owner of Devastating Pyrotechnics, one of the companies that operated out of the site.
He was identified by prosecutors as the leader, alongside Lee and Tollefson with Chan’s support. Cutright and Botelho were identified as associates, with the former also owning Blackstar Fireworks — another company that operated out of the Esparto property.
The Machados, Lee, Cutright and Tollefsen made their first court appearance on Monday.
Tammy Machado pleaded not guilty to charges levied against her, while the others did not enter a plea. Chan appeared in court on Tuesday after being arrested in Santa Clara County last week. All six are set to return to court on Thursday for arraignment or other hearings.
Chee was arrested at Disney World in Florida last Thursday on a fugitive from justice charge. He briefly appeared in Orange County court Friday, where a judge told Chee he would likely be meeting with an extradition team this week.
Botelho is in custody in Del Norte County where he was arrested in December in connection to the Esparto investigation.
District Attorney Jeff Reisig also told the Sacramento Bee he had requested both the California Attorney General’s Office and federal Department of Justice to get involved in the investigation, but these requests were declined.
Michael Vitello is a Distinguished Professor of Law at McGeorge School of Law. He spoke with Insight Host Vicki Gonzalez about the legal maneuvering behind this case.
This interview has been edited for length and clarity.
Interview highlights
Five people were charged with second-degree murder. Was that a surprise for you?
It actually was. When you hear about a death that occurs from an accident usually you think about tort damages, private right of action or involuntary manslaughter. But murder is not always intentional killing. There is another form of murder… where “malice aforethought” is not really [that], but instead it is acting with such extreme indifference to human life. It's a subtle distinction between the lack of care that might be involuntary manslaughter, and such extreme indifference that it becomes murder.
That would seemingly be the theory here. A million pounds of explosives… [in] the indictment there will be allegations that it was improperly maintained.
The DA could have gone before a judge, but instead impaneled a criminal grand jury. What is behind this approach?
Very often the use of a grand jury in California is [because] an extensive investigation might tip off people’s hands… grand jury secrecy is a way to avoid publicizing what's going on. In the federal system to bring a criminal charge, you need a grand jury, that's in the Fifth Amendment to the Constitution, but states are not obligated to do that. So it's done fairly rarely. This would be the kind of case, such a big case where you would bring so many witnesses forward, the information doesn't come out until much later.
Prosecutors are alleging that behind this deadly blast is a decade-long criminal conspiracy and an illegal black-market enterprise. How do they go about proving that in court? And how might the defense argue otherwise?
There are so many ways in which you can prove it. One of the more interesting things will be who they're going to get to testify. I don't know whether they're going to do it in this case… but very often what you do is you get people who may have had a marginal role in the case and they start to provide information because you have some leverage.
You might suggest, “maybe we won't bring criminal charges against you,” or maybe there's some simple fact witnesses who are perfectly willing to come forward. It’s very hard to know in the abstract how they'll prove it, but it's a massive conspiracy, a lot of people involved and there's so many interesting strategic choices.
For example, are you going to bring this all as one huge case in a single courtroom, which then adds lots of problems for managing the case? Are you going to separate the charges, maybe start with low-level offenders, and then build [and] climb the ladder?
Given that this is such a high-profile case, in a relatively small and rural county, do you think there's a possibility the trial might get moved elsewhere because of this attention?
It could. There's a fairly heavy burden on the part of the defendants if they want to move the case. They have to really show that the publicity is so extensive that they can't really impanel a fair jury.
Look, there's some crimes where everybody's heard of it. So what they have to do when they're trying to seat the jury [is] talk to individual jurors about whether they would be biased because of the publicity. If merely having heard about the case was enough to disqualify the jury or to move the case, you'd never have a trial. Is this a winning argument? I don't know whether they'll show enough information to move the case.
Do you think they may charge other people in the future?
You suspect that there are other people involved. How broad you want to make your charges, how many marginal players you want to bring in is always a strategic, hard choice. One reason to bring in additional people who may have had a role is to give them some quid pro quo in making sure they become cooperating witnesses. But those are things that are just not going to be out in the public for a long time.
Do you think a plea deal will be on the table for some of the people charged in this case?
Clearly for some. Way over 90% of all criminal cases are resolved by guilty pleas, and it really depends on so many factors. Very often if you are one of the most at-risk defendants who is not likely to be given a decent plea deal, and you have the resources to hire really high-powered attorneys, your incentive to go to trial goes way up. It's so hard to tell at this point.
I would think that there might even be some interest on the part of the DA's office to bring this case at least against some of the defendants, because it reassures the public to some degree that police and prosecutors and other investigators are really doing their job if something as horrible as this has taken place. Public trials have a certain virtue.
The DA told the Sacramento Bee he contacted the state Department of Justice and federal officials to conduct an investigation in Esparto, but they declined. Does that strike you as odd, given the level of this disaster and how many agencies were involved?
It’s an unusual case, it’s so hard to generalize. I think probably the federal government for a number of reasons would not be all that interested in getting involved because state resources are there. And the federal government, as you may have noticed, has some other law enforcement priorities these days. Something that can be contained to one area of California just doesn't raise the same national interest. Very often both federal and state prosecutors can move forward on a case, but there is a good bit of incentive not for both of them to be involved.
Having heard some of the news reporting, I think Jeff Reisig was concerned maybe about the overwhelming amount of work that had to be done by a relatively small office. Yolo County is not the largest district attorney's office in the world by any means. Watching the various participants [and investigators] from the DA's office, they're working hard. It’s no wonder he wanted to look for some additional help.
